You have probably heard about the superflash many times in recent months. This term is not used by astronomers, but here are some facts about what will actually happen.
The full moon occurs when the Sun, the Earth and the Moon line up in one line. If at this moment to observe from the surface of the Earth, the moon will be fully illuminated. This is because the sun in the sky will be located opposite the moon, while the moon will rise in the east, the sun will set in the west. And in about 12 hours, the Moon will set in the west and the Sun will rise in the east.
Since the Earth constantly revolves around the Sun, and the Moon constantly revolves around the Earth, the full moon is an instant event. This week it will happen at 21:35 Moscow time on Saturday, August 29th. A minute before this moment, the Moon will be in “the growing phase”, and in a minute in “decreasing”.
Each full moon occurs approximately 29.53 days after the previous full moon. This is because the orbit of the moon around the earth does not have the shape of an ideal circle, but an elliptical shape. Thus, the exact time of the full moon varies from month to month.
The most interesting result of the elliptical orbit of the moon is that the moon is sometimes closer to the earth, and sometimes further. The moment when our satellite is closest to the Earth is called “perigee”, and the moment when further - “apogee”. Amateur astronomers are most interested in finding out the date and time when the moon is closest to Earth. This month, the perigee will occur on August 30 at 18:00 Moscow time. At this time, the moon will be at a distance of about 358, 290 km from Earth.
Please note that the moon at this time will not be full.
An event like full moon and perigee can occur at the same time, and here it will be called “superfluge”. This month, the best time to observe this event will be the morning of August 30 (Moscow time), when the Moon will be between the full moon (21:35 August 29) and the perigee (18:00 August 30).
At the time of perigee, the moon will be at a distance of less than 360,000 km. When our satellite is so close, its influence on the Earth reaches its peak, the ocean tides reach their maximum value. On this day and three days later, the tides on Earth are greater than usual.
Looking ahead, we will say that next month the full moon will occur on September 28 at 05:51 Moscow time, and the perigee 51 minutes before that moment. This perigee will be closer than the one that occurred in 2015. The result will be the largest full moon of the year and stronger tides. Please note that both events will occur in the morning when the moon is visible.
